Technical Field
This disclosure relates generally to graphics processing and more specifically to texture sampling.
Description of the Related Art
Graphics textures are commonly used to render scenes for display. Textures are typically stored images that are “wrapped around” the surfaces of objects in a scene being rendered and represent a continuous function whose value is known only at the stored locations, which are called “texels.” The determination of which texels contribute to which parts of a rendered surface is typically referred to as texture mapping. Once the mapping of a given pixel in screen space to coordinates in a texture is determined, values of nearby texels in the texture are typically used to determine values for the pixel. This process is referred to as sampling and may involve the application of various filters to determine pixel attributes based on multiple texels (e.g., bi-linear, bi-cubic, etc.).
Often, to approximate an area sample over a domain, the texture function is sampled a number of times in the domain. This may be performed within a loop of graphics instructions, for example, where each loop iteration samples a texture and the results are aggregated (e.g., using a weighted average). Development of sample distributions that minimize approximation error while avoiding structured artifacts is an active research area.
Graphics circuitry that facilitates sampling techniques that utilize multiple samples within a region may be desired.